contrib/ipfilter/lib/rwlock_emul.c

   1 /*      $FreeBSD$       */
   2
   3 /*
   4  * Copyright (C) 2003 by Darren Reed.
   5  *
   6  * See the IPFILTER.LICENCE file for details on licencing.
   7  *
   8  * $Id: rwlock_emul.c,v 1.1.4.1 2006/06/16 17:21:17 darrenr Exp $
   9  */
  10
  11 #include "ipf.h"
  12
  13 #define EMM_MAGIC       0x97dd8b3a
  14
  15 void eMrwlock_read_enter(rw, file, line)
  16 eMrwlock_t *rw;
  17 char *file;
  18 int line;
  19 {
  20         if (rw->eMrw_magic != EMM_MAGIC) {
  21                 fprintf(stderr, "%s:eMrwlock_read_enter(%p): bad magic: %#x\n",
  22                         rw->eMrw_owner, rw, rw->eMrw_magic);
  23                 abort();
  24         }
  25         if (rw->eMrw_read != 0 || rw->eMrw_write != 0) {
  26                 fprintf(stderr,
  27                         "%s:eMrwlock_read_enter(%p): already locked: %d/%d\n",
  28                         rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
  29                 abort();
  30         }
  31         rw->eMrw_read++;
  32         rw->eMrw_heldin = file;
  33         rw->eMrw_heldat = line;
  34 }
  35
  36
  37 void eMrwlock_write_enter(rw, file, line)
  38 eMrwlock_t *rw;
  39 char *file;
  40 int line;
  41 {
  42         if (rw->eMrw_magic != EMM_MAGIC) {
  43                 fprintf(stderr, "%s:eMrwlock_write_enter(%p): bad magic: %#x\n",
  44                         rw->eMrw_owner, rw, rw->eMrw_magic);
  45                 abort();
  46         }
  47         if (rw->eMrw_read != 0 || rw->eMrw_write != 0) {
  48                 fprintf(stderr,
  49                         "%s:eMrwlock_write_enter(%p): already locked: %d/%d\n",
  50                         rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
  51                 abort();
  52         }
  53         rw->eMrw_write++;
  54         rw->eMrw_heldin = file;
  55         rw->eMrw_heldat = line;
  56 }
  57
  58
  59 void eMrwlock_downgrade(rw, file, line)
  60 eMrwlock_t *rw;
  61 char *file;
  62 int line;
  63 {
  64         if (rw->eMrw_magic != EMM_MAGIC) {
  65                 fprintf(stderr, "%s:eMrwlock_write_enter(%p): bad magic: %#x\n",
  66                         rw->eMrw_owner, rw, rw->eMrw_magic);
  67                 abort();
  68         }
  69         if (rw->eMrw_read != 0 || rw->eMrw_write != 1) {
  70                 fprintf(stderr,
  71                         "%s:eMrwlock_write_enter(%p): already locked: %d/%d\n",
  72                         rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
  73                 abort();
  74         }
  75         rw->eMrw_write--;
  76         rw->eMrw_read++;
  77         rw->eMrw_heldin = file;
  78         rw->eMrw_heldat = line;
  79 }
  80
  81
  82 void eMrwlock_exit(rw)
  83 eMrwlock_t *rw;
  84 {
  85         if (rw->eMrw_magic != EMM_MAGIC) {
  86                 fprintf(stderr, "%s:eMrwlock_exit(%p): bad magic: %#x\n",
  87                         rw->eMrw_owner, rw, rw->eMrw_magic);
  88                 abort();
  89         }
  90         if (rw->eMrw_read != 1 && rw->eMrw_write != 1) {
  91                 fprintf(stderr, "%s:eMrwlock_exit(%p): not locked: %d/%d\n",
  92                         rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
  93                 abort();
  94         }
  95         if (rw->eMrw_read == 1)
  96                 rw->eMrw_read--;
  97         else if (rw->eMrw_write == 1)
  98                 rw->eMrw_write--;
  99         rw->eMrw_heldin = NULL;
 100         rw->eMrw_heldat = 0;
 101 }
 102
 103
 104 void eMrwlock_init(rw, who)
 105 eMrwlock_t *rw;
 106 char *who;
 107 {
 108         if (rw->eMrw_magic == EMM_MAGIC) {      /* safe bet ? */
 109                 fprintf(stderr,
 110                         "%s:eMrwlock_init(%p): already initialised?: %#x\n",
 111                         rw->eMrw_owner, rw, rw->eMrw_magic);
 112                 abort();
 113         }
 114         rw->eMrw_magic = EMM_MAGIC;
 115         rw->eMrw_read = 0;
 116         rw->eMrw_write = 0;
 117         if (who != NULL)
 118                 rw->eMrw_owner = strdup(who);
 119         else
 120                 rw->eMrw_owner = NULL;
 121 }
 122
 123
 124 void eMrwlock_destroy(rw)
 125 eMrwlock_t *rw;
 126 {
 127         if (rw->eMrw_magic != EMM_MAGIC) {
 128                 fprintf(stderr, "%s:eMrwlock_destroy(%p): bad magic: %#x\n",
 129                         rw->eMrw_owner, rw, rw->eMrw_magic);
 130                 abort();
 131         }
 132         memset(rw, 0xa5, sizeof(*rw));
 133 }